European patent application EP 2 527 058 A1 relates to a machine tool in the form of a press for processing workpieces, in particular metal sheets. A pressing tool is actuated by means of a wedge gear comprising two drive side gear wedges and two tool side gear wedges. The tool side gear wedges support the pressing tool. The drive side gear wedges are each provided with a spindle nut of a drive system in the form of a spindle drive. The spindle nuts are seated on a common drive spindle and each have a drive motor, by means of which they can be moved along the drive spindle jointly with the drive side wedge gears. Movements, which the drive side gear wedges perform simultaneously along the drive spindle and at relative to the tool side gear wedges, generate movements of the pressing tool in the transverse direction of the drive spindle due to the cooperation of the drive side gear wedges and the tool side gear wedges. If the drive side gear wedges are moved simultaneously and in the same direction along the drive spindle, the drive side gear wedges take the tool side gear wedges, and via these, the pressing tool, with them in the direction of movement. In this way, the pressing tool can be positioned along the drive spindle.
Trouble-free workpiece processing by means of the pressing tool and/or high processing precision require high positioning accuracy of the drive side gear wedges, and thus high positioning accuracy of the drive system used to move the drive side gear wedges.